Results 21 to 30 of about 47,444 (303)

EDEN Survey: Small Transiting Planet Detection Limits and Constraints on the Occurrence Rates of Planets around Late-M Dwarfs within 15 pc

The Astronomical Journal, 2023
Earth-sized exoplanets that transit nearby, late-spectral-type red dwarfs will be prime targets for atmospheric characterization in the coming decade.
Jeremy Dietrich, Dániel Apai, Martin Schlecker, Kevin K. Hardegree-Ullman, Benjamin V. Rackham, Nicolas Kurtovic, Karan Molaverdikhani, Paul Gabor, Thomas Henning, Wen-Ping Chen, Luigi Mancini, Alex Bixel, Aidan Gibbs, Richard P. Boyle, Samantha Brown-Sevilla, Remo Burn, Timmy N. Delage, Lizxandra Flores-Rivera, Riccardo Franceschi, Gabriele Pichierri, Sofia Savvidou, Jonas Syed, Ivan Bruni, Wing-Huen Ip, Chow-Choong Ngeow, An-Li Tsai, Chia-Lung Lin, Wei-Jie Hou, Hsiang-Yao Hsiao, Chi-Sheng Lin, Hung-Chin Lin, Ritvik Basant, Project EDEN   +32 more
doaj   +1 more source

X‐Ray Spectroscopy of Rapidly Rotating, Late‐Type Dwarf Stars

The Astrophysical Journal, 1999
We present an X-ray spectroscopic analysis of two active dwarf stars with extremely short rotation periods, HD 197890 (Speedy Mic) and Gliese 890, using X-ray data acquired with the ASCA observatory. We analyze the X-ray spectrum of Speedy Mic in two separate time intervals, one corresponding to an apparent stellar flare, the other to "quiescence" or ...
K. P. Singh, S. A. Drake, E. V. Gotthelf, N. E. White   +3 more
openaire   +1 more source

Titanium abundances in late-type stars

Astronomy & Astrophysics, 2022
Context. The titanium abundances of late-type stars are important tracers of Galactic formation history. However, abundances inferred from Ti I and Ti II lines can be in stark disagreement in very metal-poor giants. Departures from local thermodynamic equilibrium (LTE) have a large impact on the minority neutral species and thus influence the ...
Mallinson, J. W. E., Lind, K., Amarsi, Anish, Barklem, Paul, Grumer, Jon, Belyaev, A. K., Youakim, K.   +6 more
openaire   +3 more sources

A wide-area view of the Phoenix dwarf galaxy from VLT/FORS imaging [PDF]

, 2012
We present results from a wide-area photometric survey of the Phoenix dwarf galaxy, one of the rare dwarf irregular/ dwarf spheroidal transition type galaxies (dTs) of the Local Group (LG).
Akaike, Appenzeller, Battaglia, Battaglia, Bellazzini, Bellazzini, Bernard, Caldwell, Cannon, Caon, Cardelli, Cole, Coleman, Coleman, Coleman, Cooper, Da Costa, de Boer, Demers, E. Tolstoy, Freudling, G. Battaglia, G. Beccari, Gallart, Gallart, Gallart, Girardi, Girardi, Graham, Harbeck, Held, Hidalgo, Holtzman, Irwin, Irwin, Jerjen, Karachentsev, Kazantzidis, King, Leaman, Lee, M. J. Irwin, M. Rejkuba, Majewski, Marigo, Martínez-Delgado, Martínez-Delgado, Mateo, Mayer, Menzies, Monelli, Monelli, Pietrinferni, Pietrinferni, Plummer, Robin, Salaris, Schlegel, Schroyen, Sersic, Stanek, Stetson, Stetson, Stetson, Stinson, Tolstoy, Trujillo, van de Rydt, Wilkinson, Young   +69 more
core   +3 more sources

Microwave emission from the coronae of late-type dwarf stars

The Astrophysical Journal, 1983
VLA microwave observations of 14 late-type dwarf and subgiant stars and binary systems are examined. In this extensive set of observations, four sources at 6 cm (Chi-1 Ori, UV Cet, YY Gem, and Wolf 630AB) were detected and low upper limits for the remaining stars were found.
J. L. Linsky, D. E. Gary
openaire   +1 more source

Radio Detection of Late-Type (G--K) Dwarf Stars in the Pleiades

The Astrophysical Journal, 1995
We report deep 3.6 cm radio observations of a small sample of the most rapidly rotating G-K dwarf stars in the Pleiades. Of the four ultrafast rotators (UFRs) observed, three were detected. The G8 dwarf H II 1136, the fastest rotating G dwarf known in the Pleiades, displayed a flare that rose to a peak flux density of ∼1 mJy (peak radio luminosity of ...
Lim, J, White, SM
openaire   +2 more sources

Detailed Analysis of Nearby Bulgelike Dwarf Stars II. Lithium Abundances [PDF]

, 2002
Li abundances are derived for a sample of bulgelike stars with isochronal ages of 10-11 Gyr. These stars have orbits with pericentric distances, Rp, as small as 2-3 kpc and Zmax < 1 kpc.
Barbuy B., Beatriz Barbuy, Bruno Vaz Castilho, Carlsson M., Castilho B. V., Cayrel R., Cayrel R., D’Antona F., Favata F., Garcia Lopez R. J., Gustafsson B., James D. J., Jeffries R. D., Lambert D. L., Lambert D. L., Luciana Pompeia, Michel Grenon, Pasquini L., Pasquini L., Proffitt C. R., Randich S., Randich S., Soderblom D. R., Spite F., Spite F., Thorburn J. A.   +25 more
core   +2 more sources

CCD Parallaxes for 309 Late-type Dwarfs and Subdwarfs

, 2017
New, updated, and/or revised CCD parallaxes determined with the Strand Astrometric Reflector at the Naval Observatory Flagstaff Station (NOFS) are presented. Included are results for 309 late-type dwarf and subdwarf stars observed over the 30+ years that
Ables, Harold D., Canzian, Blaise J., Dahn, Conard C., Guetter, Harry H., Harris, Fred H., Harris, Hugh C., Henden, Arne H., Leggett, S. K., Levine, Stephen E., Luginbuhl, Christian B., Monet, Alice B., Monet, David G., Munn, Jeffrey A., Pier, Jeffrey R., Stone, Ronald C., Subasavage, John P., Tilleman, Trudy M., Vrba, Frederick J., Walker, Richard L.   +18 more
core   +1 more source

The Y-Band at 1.035 um: Photometric Calibration and the Dwarf Stellar/Sub-Stellar Color Sequence [PDF]

, 2002
We define and characterize a photometric bandpass (called "Y") that is centered at 1.035 um, in between the traditionally classified ``optical'' and ``infrared'' spectral regimes.
Bahng J., Jonathan B. Foster, K. Matthews, Lynne A. Hillenbrand, S. E. Persson, Selby J. E. A.   +5 more
core   +2 more sources

Spectral classification of Pleiades brown dwarf candidates

, 2011
We report on the results of the spectroscopy of 10 objects previously classified as brown dwarf candidates via RIJHK colors by Eisenbeiss et al. (2009), who performed deep imaging observations on a 0.4 sq.deg. field at the edge of the Pleiades.
An, Bertin, Cruz, Cushing, Deacon, Eisenbeiss, Gizis, Hamilton, Hodgkin, Hog, Izzo, Kirkpatrick, Kirkpatrick, Lasker, Lawrence, Martín, Martín, Moualla, Pickles, Prosser, Rayner, Rebolo, Reid, Reid, Rieke, Robichon, Röser, Röser, Schilbach, Stauffer, Steele, van Leeuwen, Zacharias   +32 more
core   +1 more source